150Parameters affecting the sulphate removal during the biological treatment of industrial wastewater are not well known and might hamper the biological system. This research shows the effect of transient feeding conditions on the sulphate removal using sequencing batch reactors (SBR). Six SBR were used, R1L (1 g CODLactate.L−1, 0.4 g SO42−.L−1 and 0.3 g NH4Cl.L- 1) and R1H (6 g CODLactate.L−1 and 2.5 g SO42−. L−1 and 1.8 g NH4Cl.L−1) were used as control and steady feeding. The SBR R2L and R3L operated at feast (6 g CODLactate.L−1 and 2.5 g SO42− .L−1) and famine conditions (zero concentration). The SBR R2H and R3H operated at higher feast concentrations (36 g CODLactate.L−1 and 15 g SO42−. L−1) and also famine conditions (zero concentration). The SBR R2L and R2H were feed with 1.8 g NH4Cl.L−1 meanwhile, the SBR R3L and R3H with 0 g NH4Cl.L−1, during the feast conditions. The sulphate removal efficiency (SRE) was robust to transient feeding conditions in R2L and R3L, it was 92% at feast and 86- 90% at famine conditions in both SBR while 94 (± 8)% at the control reactor R1H. The SRE was 79 (± 17)% in R1L, dropped to ˂ 20% in R2H and it was maintained at slightly above 40% in R3H.